Pens and pencils are popular novelty items used to advertise companies, political parties and the like as well as display various design elements and logos that motivate people to purchase and/or use the instrument. In many cases, these pens and pencils are used to create good will between the perceived donor of the writing instrument and potential or actual customers or other recipients to whom they are given. Accordingly, there is a constant search for novel writing instruments that can be used to attract attention and foster good while meeting practical budget constraints of the donor
This invention is more specifically directed to writing instruments having a retractable writing tip. Some pens, such as ballpoint pens, and some types of pencils include a retractable writing tip that is operated by the downward pressing of a manually actuated button at the top of the instrument or, alternatively, by the rotation of a part of the writing instrument's body with respect to another part of the body. For clarity, the terms “top” and “bottom” will be used in the context of a pen's conventional writing position with its writing point at the bottom, although it is clear that the pen can be oriented otherwise during use and/or storage.
FIG. 1 hereto is an example of a prior art ballpoint pen, and is utilized to identify the basic parts of the pen as comprising a generally tubular body 10 disposed about a longitudinal axis 25, and consisting of a lower body portion 11 and an upper body portion 13. The upper and lower body portions are typically separable, with the top portion typically screwing into the bottom portion or vice-versa. A clip 14 is secured to the upper body portion by any of a number of suitable and well-known methods. A cartridge unit 20 having an ink reservoir is positioned within the body 10 of the pen, and terminates at its bottom in a writing tip 22. The cartridge forms a reservoir 21 for the ink dispensed by the pen at its tip, and is typically replaceable when the upper and lower body portions are separable.
The cartridge unit 20 is mounted for longitudinal sliding reciprocal movement within the body 10 of the pen. A spring 24 surrounds the lower end of the cartridge, and is captured between the lower narrowed end of the lower body 11 and a radially enlarged portion 23 of the cartridge unit 20. The spring 24 is sufficiently compressed to urge the cartridge upward and, consequently, to urge the writing tip upward into a retracted position within the bottom region of the lower body portion 11.
The upper body portion 13 typically contains the protracting and retracting mechanism by which the writing tip is selectively deployed and retracted in the longitudinal direction, and numerous structures for accomplishing this function are known in the art. As will be apparent, the invention herein is not limited to any particular protraction/retraction mechanism, but is responsive to the longitudinal movement of the cartridge or equivalent pencil structure however induced. In FIG. 1, the longitudinal movement is induced by the manual pressing of button 30 which protrudes through a central hole formed in the top of the pen's body. As known to those of ordinary skill in the art, the pressing of the button causes the interior end of the button to push downward on the cartridge unit 20 against the spring 24. When the button is released, and the spring moves the cartridge upward, the cartridge's upward progress is blocked by a gearing arrangement that has been rotated during the downward longitudinal movement so as to now engage an interior blocking surface formed on the inner surface of the pen's upper body. The result is the deployment of the writing tip in its protracted position. When the button 30 is pressed again, the gear again rotates to clear the blocking surface as the button is released, resulting in a full retraction of the writing tip. As noted above, the many mechanisms for carrying out this function are well known in the art, and a detailed description is unneeded.